Scientists from the Paris Observatory used the NASA/ESA Hubble Space Telescope to take a look at the auroras on Uranus, which are caused by streams of charged particles like electrons that come from various origins such as solar winds, the planetary ionosphere, and moon volcanism.

How Uranus was nearly called Georgium Sidus

Uranus was discovered in 1781 by astronomer William Herschel, who originally thought it was a comet or a star. He wanted to name it Georgium Sidus, after King George III but it was eventually named after Uranus, the Greek god of the sky, as suggested by astronomer Johann Bode, who was instrumental in working out Uranus was indeed a planet.

The particles become caught in powerful magnetic fields and are channelled into the upper atmosphere, where their interactions with gas particles, such as oxygen or nitrogen, set off spectacular bursts of light.

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The auroras on Jupiter and Saturn have been well-studied, but the auroras on the giant ice planet Uranus remain something of a mystery.

The first images of Uranus taken from Earth were shot in 2011 by the NASA Hubble.

In 2012 and 2014 a team led by an astronomer from Paris Observatory took a second look at the auroras using the ultraviolet capabilities of the Space Telescope Imaging Spectrograph (STIS) installed on Hubble.

Uranus as viewed by Voyager 2 (Picture NASA)

They tracked the interplanetary shocks caused by two powerful bursts of solar wind travelling from the sun to Uranus, then used Hubble to capture their effect on Uranus’ auroras – and found themselves observing the most intense auroras ever seen on the planet.

By watching the auroras over time, they collected the first direct evidence that these powerful shimmering regions rotate with the planet.

Has Uranus been probed?

At its closest, the spacecraft came within 81,500 kilometres (50,600 miles) of Uranus’s cloudtops on January 24, 1986.

Voyager 2 radioed thousands of images and voluminous amounts of other scientific data on the planet, its moons, rings, atmosphere, interior and the magnetic environment surrounding Uranus.

A map of the outer solar system (Picture: AFP/Getty)

Since launch on August 20, 1977, Voyager 2’s itinerary has taken the spacecraft to Jupiter in July 1979, Saturn in August 1981, and then Uranus. Voyager 2’s next encounter was with Neptune in August 1989. Both Voyager 2 and its twin, Voyager 1, will eventually leave our solar system and enter interstellar space.

Voyager 2’s images of the five largest moons around Uranus revealed complex surfaces indicative of varying geologic pasts. The cameras also detected 10 previously unseen moons.

The 11 rings of Uranus, opaque and a few kilometres wide each, are relatively young in space terms – not more than 600 million years old. They were probably formed by collisional fragmentation of several moons that once orbited the planet (Picture: BSIP/UIG Via Getty)

Several instruments studied the ring system, uncovering the fine detail of the previously known rings and two newly detected rings.

The spacecraft also found a Uranian magnetic field that is both large and unusual. In addition, the temperature of the equatorial region, which receives less sunlight over a Uranian year, is nevertheless about the same as that at the poles.